Video games are a popular entertainment in the modern households. There are many different types of electronic game devices available in the market, including plug and play, handheld LCD game, consoles and household entertainment systems such as X-Box and PlayStation. These video games devices may have different electronic designs but they share a same feature that, during the playing of the games, video images are typically generated in real time through sprite animation by their respective electronic game processors based on their respective digital video data and game control programs stored in their respective memories.
Wikipedia (en.wikipedia.org) states that, in computer graphics, a “sprite” is a two-dimensional image or animation that is integrated into a larger scene.
Sprites are originally invented as a method of quickly compositing several images together in two-dimensional video games using special hardware. As computer performance improved, this optimization became unnecessary and the term evolved to refer specifically to the two dimensional images themselves that are integrated into a scene. That is, figures generated by either custom hardware or by software alone are all referred to as sprites. As three-dimensional graphics became more prevalent, the term was used to describe a technique whereby flat images are seamlessly integrated into complicated three-dimensional scenes.
It is a general believe that video clips are not suitable for the making of interactive action games. In fact, there are some basic limitations and problems to use a video clip to construct an interactive video game.
1) A video clip is basically a pre-recorded movie, which may consist of real people and/or animals in a real scene or animated people and/or animals in a virtual scene, or a combination thereof. Because the video clip is a pre-recorded movie, it is very difficult, if not impossible, to directly make any instantaneous change to the contents in a particular frame in a real time application. This is because an interactive video game typically involves a series of real time actions and reactions between a game player and a game play, and the actions and reactions need to be shown in real time through a game unit.
2) In sprite animated video game design, the game designer and/or programmer must lay down the details for the game flow and game data before hand. Such game data may include: when a certain action is going to occur in the game, where on the video screen the animations will show up or move around, and what interactive movements or actions the animation need to perform. In other words, all the game actions and game flow data must be made available before a game program can be developed. But the video clip itself does not provide such information at all.
3) Assuming that in a simple sprite animation driving video game, the game player wants to steer his car from one lane to another lane on a road, which typically involves the use of an electronic game processor in the video game unit to read the steering wheel input from the game player. Then the game processor will process the steering input data according to a game control program and aesthetic and/or graphical data available in the game memory to create the scene of a car changing lane in virtually real time. To construct a similar video game using video clip, it is necessary to make at least 2 pre-recorded video clips because it is impossible to make any instantaneous change to the contents of the video clip as in the sprite animated video game. The first video clip is to show the car running on the original lane, and the second video clip is to show the car to change lane. When the game player steers the steering wheel, the game processor detects the steering input and then switches from playing the current video clip to playing the next video clip which shows the car to change lane. Since it takes a given time to switch from one video clip to another, this means there can be a delay in response time when it is necessary to switch from one video clip to another video clip.
4) In order to make the above steering action more realistic, it requires more than one steering angle and to collect other parameters such as a speed at which the car is running. If each steering angle and the running speed respectively require a separate video clip, this will need a large amount of video clips and will certainly become impractical, and the production cost will be increased dramatically.
The moving objects in a typical video game are made up of sprites that can move independently on the game scene background. In other words, the animations are generated in real time by the game processor using multi-layers of overlaying background images and sprite animations. In the video game design, sprites typically refer to characters and other moving objects in a game. The size of the sprite being animated in the game can have a significant impact on the processing speed at which a sprite is animated. Smaller sprite can be animated faster than larger sprites. This is because the game processor only needs to manipulate less graphic data with smaller sprites than with larger ones. Sprite size is typically defined in number of pixels, such as 16×16 pixels, 128×64 pixels and etc. Because the size of the sprite can impact the speed at which a sprite is animated, most video games employs relatively small sprites to avoid the needs of using a high speed game processor and a memory of large capacity in the electronic design which can significantly increase the costs of a product.
Due to this constrain in sprite size and speed in animation, the graphic quality and smoothness in motion animation are compromised for most of the video games. For example, dance game is a popular video game. There are various dance games available in the market. In the real world, a dance always involves different parts of a human body to move in a series of coordinated movements. Such complex movements are difficult to animate using sprites. Therefore most interactive video dance games in the market only employ geometric symbols, typically in the forms of directional arrows, such as Up, Down, Left and Right pointing arrows, in their interactive video scenes to represent the dance steps for the game player to follow instead of showing the actual dance steps by the dancer.
The technically advanced and expensive video gaming systems like X-Box and PlayStation also use directional arrows of sprite animations in their dance games to represent the dance steps. Although they display some high quality animated dancers in the dance games, the animated dancers do not dance in synchronization with the directional arrows or do not show the actual dance steps in the games.
On the other hand, the complex movements of the dancer in the real world can be captured in high fidelity in a video clip. Alternatively, 3D computer model can be employed to animate the complex movements of a virtual dancer using computer softwares to produce some animated movies.
Because of the above constrains and problems, it has not been found in the art that a video clip is directly used to construct an interactive video game.